<g:formRemote url="${[action:'saveTags']}"
    name="saveTags"
    controller="post"
    action="saveTags"
    id="${post.id}"
    update="tags${post.id}">
  <g:hiddenField name="id" value="${post.id}"/>
  <input type="text" name="tagString" value="${post.tagsAsString()}"/>
  <input type="submit" value="Update"/>
  <g:remoteLink controller="post"
      action="showTags"
      id="${post.id}"
      update="tags${post.id}">
    Cancel
  </g:remoteLink>
</g:formRemote>